Protecting device for furnaces



No. 62u59. P

atented June 2 l J. s. UNGER. 0 899 PROTEGTING DEVICE FOB FURNACES` (Application led June 9, 1898.) (No Model.)

WITNESSES INVENTR me Nonms usas co.. PHOTO uwn., wAsmNnvoN, n. c.

UNITED STATES PATENT OFFICE.

JOHN S. UNGER, OF HOMESTEAD, PENNSYLVANIA, ASSIGNOR TO THE OARd NEGIE STEEL COMPANY, LIMITED, OF PITTSBURG, PENNSYLVANIA.

PROTECTING DEVICE FOR FURNACES.

SPECIFICATION forming part of Letters Patent No. 627,159, dated June 20, 1899.

Application filed June 9,1898. Serial No. 682,984. (Normodel.)

To a/ZZ whom t may concern.:

Be it known that I, JOHN S. UNGER., of Homestead, in the countyof Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Protecting Devices for Furnaces, of which the following is a full,clear, and exact description, reference being had to the accompanying drawing, forming part of this specification, which shows in vertical section a furnace provided with my improvement. i

The object of my invention is to provide means for protecting metal parts of furnaces which are exposed to great heat.

I have specially designed the invention for the protection of the gas-supply pi pe by which hydrocarbon gas is delivered to the space between armor-plates or like masses of steel while undergoing the gas-carburization process in a heating-furnace. The cutting action of the intensely hot gases in such furnace is very destructive to the gas-supply pipes, and the various expedients which have been tried heretofore for the protection of such pipes, such as the use of water-jackets and asbestos Wrapping's, have not proved satisfactory.

My invention consistsV in applying to the surface to be protected a jacket of carbon, which, by furnishing carbon to combine with and neutralize all oxidizing-gases which may penetrate to the metal surface, affords a complete protection.

The mode in which I prefer to apply the invention to practice, and which I claim herein specifically, is to place around the gassupply pipe an outer pipe or sheath and fill the intermediate space With bituminous coal or like coking material, so that when heated it will be converted 'in situ into a jacket of coke, which, as it swells somewhat in coking, will make a very tightly fitting covering for the pipe.

In the drawing, 2 represents a heating-furnace of the usual construction.

3 3 are armor-plates supported on a hearth 4. and separated by supporting blocks or billets 5, so as to afford an intermediate space 6, into which the carburizin g hydrocarbon gas is delivered from a pipe 7. Around the pipe 7 I place an outer pipe-or sheathing 8 of larger diameter and I fill the space between the pipes with a'body of bituminous coal 9. When the pipe so arranged is in the furnace, the intense heat of the latter will soon coke the coal, driving oif the volatile gases, which escape at the ends of the sheathing, and leaving in the sheathing a closely-fitting jacket of'carbon, which will prevent access to the pipe of any oxidizing gases. A pipe thus protected will be found at the end of a run of the furnace to-be quite unburned, and although the exterior sheathing 8 may be oxidized this is a matter of but little moment, as it may be made of cheap material and is therefore easy to replace.

For the purpose of cleaning the interior of ythe pipe from the carbon which is deposited therein by decomposition of the hydro-carbon gas I provide at its rear end a removable plug 10, on removing which a cleaningrod may be pushed through the pipe.

Modifications of my invention in order to adapt it to other parts or places of a furnace structure may be made by those skilled in the art, as will be readily understood, since 1. As a protecting device for metal parts exposed to hot gases in furnaces, the combination with the metal part of a sheath and a jacket of carbonaceous material interposed between the part to be protected and the sheath, and adapted to be coked in Situ; substantially as described.

2. As a protecting device for metal parts exposed to hot gases in furnaces, the combination with the metal part of a sheath and a jacket of coal interposed between the part to be protected and the sheath, and adapted to be coked fm Sita; substantially as described.

In testimony whereof I have hereunto set Vmy hand.

JOI-IN S. UNGER. Vitnesses:

THOMAS W. BAKEWELL, H. M. CoRWIN. 

